双金属クロム触媒を用いたプロピレン酸化物の同型連鎖シャトルポリメリゼーション:半結晶ポリオールへの新しい経路

M Ian Childers¹, Andrew K Vitek², Lilliana S Morris¹

¹Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853-1301, United States.

Journal of the American Chemical Society

|July 4, 2017

まとめ

研究者らは,ラセミックプロピレン酸化物からヒドロキシテレケリック同質性ポリプロピレン酸化物 (PPO) を合成する新しい方法を開発した. 先進的な材料の応用で分子重量と構造を制御できます

科学分野:

ポリマー化学
カタリシス
材料科学

背景:

ハイドロキシテレケリックポリオキシプロピレン (PPO) はポリウレタン合成の重要な成分である.
現在の方法では,ラセミックプロピレン酸化物からアタクティックなPPOを生産し,アイソタクティックなPPOの望ましい半結晶特性がない.
ラセミックプロピレン酸化物から水素テレケリック同質PPOへの実用的な経路が必要である.

研究の目的:

簡単に入手可能なラセミクプロピレン酸化物を用いて,ヒドロキシテレケリク同質PPOの実用的な合成を開発する.
ポリメリゼーション過程で分子量と機能性を制御する.
ポリメリゼーションのメカニズムとステレオ選択性を解明する.

主な方法:

エナチオセレクティブとイソセレクティブのバイメタリック触媒を用いて,ヒドロキシテレケリック同質PPOの合成.
ポリマーの構造と機能を制御するためにチェーンシャットリング剤 (ダイオール,トリオール,ポリマー) を利用する.
ポリメリゼーションメカニズムを調査するために詳細な量子化学研究を使用します.

主要な成果:

ラセミクプロピレン酸化物から,ヒドロキシテレケリック同位性PPOの合成を成功させた.
分子重量とポリマーの機能性 (ダイオール,トリオール,ポリマー) の制御が実証されている.
変換のための可用バイメタリッククロム触媒を特定した.

結論:

ハイドロキシテレケリック同質PPOを生産するための新しい実用的な方法が確立されています.
開発された触媒システムは,ポリマー構造の正確な制御を可能にします.
このメカニズムの理解は,高度なステレオ選択的ポリメリゼーション触媒の設計のための基礎を提供します.

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